Answer choices are ..
a ) nuclear fission because an atom splitting into two fragments
b)nuclear fusion because the products that are produced are radioactive
c) nuclear fission because a large amount of energy is being released
d) nuclear fusion because an atomic nuclei combine to form a heavier nucleus

D) nuclear fusion because an atomic nuclei combine to form a heavier nucleus

Explanation:

Nuclear fusion is a process which involves the conversion of two small nuclei to form a heavy nuclei along with release of energy.

Nuclear fission is a process which involves the conversion of a heavier nuclei into two or more small and stable nuclei along with the release of energy.

As in the given reaction a heavier nuclei helium is being formed from combination of deuterium and tritium, this is a nuclear fusion reaction.

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.